This invention relates to a collapsible frame assembly disposable on a horizontal surface for holding a protective cover sheet such as a tablecloth at a height and in a manner to protect items such as food on the horizontal surface. More particularly, this invention relates to such a collapsible frame assembly attachable to a serving cart for supporting a protective sheet or cloth which covers a horizontal table surface of the serving cart.
The purpose of holding a tablecloth or other sheet above food on a table surface is to provide a screen to protect the food, for example, from insects. The cover sheet may also serve to facilitate the retention of heat by the food on the table surface.
An obvious method for protecting food placed on a table surface is to lay a sheet over the food. This method is clearly unsatisfactory inasmuch as the sheet is likely to come into contact with the food, thereby soiling the sheet as well as possibly distorting the appearance of the food. It is necessary, then, to provide means for holding the cover sheet away from the food on the table surface.
Support devices for providing protective shields over horizontal surfaces are known which comprise rigid dome-shaped structures. For example, U.S. Pat. No. 788,351 to Burrell discloses a rigid ribbed structure which supports a protective cover in the form of a canopy and which can be alternately raised and lowered over a table surface. Owing to its bulk, such a device is cumbersome and inconvenient.
U.S. Pat. No. 906,024 discloses two rigid frames each having four posts supporting an arcuate ribbed umbrella structure. The support posts are provided at their lower ends with clamps for mounting the frames to a table. On a table, the frames are spaced from one another to provide a support for a protective cover sheet.
Support devices have been developed which are lightweight and which can be put into storage configurations when the support devices are not being used to hold protective sheets over horizontal surfaces. U.S. Pat. No. 809,546 to Wever, for example, discloses a pair of wire brackets each provided at opposite ends with hooks or clasps for clamping the brackets to the edges of a horizontal table surface. U.S. Pat. No. 708,049 to Jordan discloses a support device comprising four wire arms each rotatably connected at one end to the other arms by a clamping element and engageable with a horizontal table surface at an opposite end. The support device of U.S. Pat. No. 708,049 is collapsible by rotating the wire arms towards each other about respective pivot axes.
U.S. Pat. No. 451,946 to Meyer discloses a pair of foldable chains of rigid straight bars hingedly connected to each other. The chains assume V-shaped configurations when placed on a table surface for holding a canopy over the table.
U.S. Pat. No. 526,942 to Rhoads et al. describes a food screen comprising a pair of cofunctioning identical collapsible support frames. The support frames are placed at opposite ends of a table and overlap one another to hold a protective sheet above and away from a food-bearing surface. Each support frame comprises a U-shaped base member and a plurality of U-shaped support members, the support members being connected at their ends to the opposite legs of the base member. The central portions of the support members are coupled to one another by a longitudinally extending brace or linking bracket, whereby the U-shaped support members may be collectively pivoted from a collapsed storage configuration to a raised operating configuration.
U.S. Pat. No. 2,683,507 to Coven et al. discloses a portable and collapsible food screen comprising a multiplicity of U-shaped ribs each rotatably connected at its opposite ends to a pair of semicircular brackets or plates. The food screen has a folded storage configuration in which the U-shaped ribs are parallel to one another and an open operational configuration in which the ribs occupy respective, angularly spaced radial planes.
An object of the present invention is to provide a simple and inexpensive collapsible frame assembly disposable in an open configuration on a horizontal surface for supporting a sheet or web in a tent-like configuration over items such as food placed on the horizontal surface.
Another object of the present invention is to provide such a collapsible frame assembly which can be mounted to or attached to serving carts of the kind used in hotels.